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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC - Time-Delay Bolt-On Fuses
MERSENTime-Delay Bolt-On Fuses

MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY4000) is a 4 kA, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in electrical systems.

SKU 3G-OTH-26383

Brand
MERSEN
Item
Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC
Category
Time-Delay Bolt-On Fuses
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

MERSEN
Manufacturer Part Number
A4BY4000
Series
A4BY
Type
A4BY Series, Bolt-On Body, Time-Delay, 4 kA
AC
600 V
DC
300 V

Technical Documents

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MERSEN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY4000) is a 4 kA, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in electrical systems.

Frequently Asked Questions

What is the MERSEN A4BY4000 fuse used for?

The MERSEN A4BY4000 is a Class L time-delay bolt-on fuse rated 4 kA, 600 V AC, 300 V DC. It provides overcurrent protection in industrial electrical systems, such as motor circuits, feeders, and switchboards, where high interrupting capacity and delayed response to inrush currents are required.

What are the specifications of the MERSEN A4BY4000 fuse?

The MERSEN A4BY4000 is a Class L, A4BY Series, bolt-on body, time-delay fuse. It has an interrupting rating of 4 kA, operates at 600 V AC and 300 V DC, and is designed for overcurrent protection in industrial electrical distribution systems.

Where to buy the MERSEN A4BY4000 fuse worldwide?

3G Electric supplies the MERSEN A4BY4000 fuse to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this Class L time-delay bolt-on fuse.

How to select the correct MERSEN A4BY4000 fuse for an application?

To select the MERSEN A4BY4000, verify your system voltage (600 V AC or 300 V DC) and required interrupting rating (4 kA). Ensure the bolt-on body matches your fuse holder. For time-delay applications like motor starting, this fuse handles inrush without nuisance opening. Consult a qualified engineer for coordination studies.

Used in

Common applications for MERSEN
Power electronics protection — MERSEN A70Q series semiconductor fuses in variable frequency drives for motor control.
Surge protection for industrial panels — MERSEN STP480D07 SPDs in three-phase 480V AC distribution boards.
Control circuit overcurrent protection — MERSEN ATM series midget fuses in PLC and instrumentation cabinets.
Power distribution in manufacturing — MERSEN FSPDB4A finger-safe blocks in motor control centers for wire management.
DC bus protection in renewable energy — MERSEN A30QS series fuses in solar inverter DC inputs.
High-voltage semiconductor protection — MERSEN A70Q series fuses in welding equipment power supplies.

MERSEN Products

3G Electric supplies MERSEN time-delay bolt-on fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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